The field of art to which this subject matter pertains is the selective hydrogenation of olefins contained in a hydrocarbon stream comprising olefins and aromatic compounds. Hydrogenation processes have been used by petroleum refiners and petrochemical producers to produce more valuable hydrocarbonaceous products. Hydrocarbonaceous streams containing olefins and aromatic compounds are only useful if the olefins can be selectively hydrogenated without the simultaneous hydrogenation of the aromatic compounds.
The higher reformer severity and lower pressure required for higher aromatics yield also promotes the formation of olefins. The resulting olefins, which are about 1-2 weight percent of the net reformate, contributes to undesirable gum and high endpoint in gasoline product as well as high clay consumption in aromatics recovery operations. Traditionally, clay treating is used when treating aromatics streams to reduce olefin content and meet feed specifications of downstream aromatics processes. However, clay treating is not ideal as it requires hazardous landfill disposal of clay, and results in the loss of valuable aromatics by alkylation with olefins.
Although a wide variety of process flow schemes, operating conditions and catalysts have been used in the selective hydrogenation of olefinic hydrocarbons, there is always a demand for new selective hydrogenation methods which provide lower costs and the required product quality, while minimizing undesirable by-products.
Accordingly, it is desirable to develop methods and apparatuses for selective hydrogenation of olefins that maximizes the production of aromatics. Furthermore, other desirable features and characteristics of the present embodiment will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background.